Rain barrels are everywhere these days, and while they are great for providing water for your lawn or garden, what about drinking water? This plan for a carbon filter was pulled from a 100 year old homesteading handbook.

I haven't personally built or tested one of these, but one of my close friends spent some time in the peace corps building similar rainwater filters in developing countries. Recently, a nearby town suffered a 48 hour "water ban" because of toxins in the water caused by a particular algae, and while my water comes from a ground well, it got me thinking about other ways to harvest drinking water.

This low-tech system uses charcoal, sand, and stone in varying layers to filter water that comes from a downspout. While there are differences between what charcoal and activated charcoal will filter (most filters use the activated version these days), I'd be interested in seeing how water from this low-tech system compares to the drinking water that comes from our faucets.